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Question-63060




Question Number 63060 by rajesh4661kumar@gamil.com last updated on 28/Jun/19
Answered by Hope last updated on 28/Jun/19
(√(((1+cosθ)^2 )/(sin^2 θ)))   =∣((1+cosθ)/(sinθ))∣  =((∣1+cosθ∣)/(∣sinθ∣))  when   π>θ>0  so sinθ=+ve  cosθ<0   but ∣cosθ∣<1  ∣1+cosθ∣=1+cosθ  so  ((∣1+cosθ∣)/(∣sinθ∣))  =((1+cosθ)/(sinθ))=cosecθ+cotθ  but when  2π>θ>π  =((∣1+cosθ∣)/(∣sinθ∣))  =((1+cosθ)/(−sinθ))  =−cosecθ−cotθ
$$\sqrt{\frac{\left(\mathrm{1}+{cos}\theta\right)^{\mathrm{2}} }{{sin}^{\mathrm{2}} \theta}}\: \\ $$$$=\mid\frac{\mathrm{1}+{cos}\theta}{{sin}\theta}\mid \\ $$$$=\frac{\mid\mathrm{1}+{cos}\theta\mid}{\mid{sin}\theta\mid} \\ $$$${when}\:\:\:\pi>\theta>\mathrm{0}\:\:{so}\:{sin}\theta=+{ve} \\ $$$${cos}\theta<\mathrm{0}\:\:\:{but}\:\mid{cos}\theta\mid<\mathrm{1}\:\:\mid\mathrm{1}+{cos}\theta\mid=\mathrm{1}+{cos}\theta \\ $$$${so}\:\:\frac{\mid\mathrm{1}+{cos}\theta\mid}{\mid{sin}\theta\mid} \\ $$$$=\frac{\mathrm{1}+{cos}\theta}{{sin}\theta}={cosec}\theta+{cot}\theta \\ $$$$\boldsymbol{{but}}\:\boldsymbol{{when}}\:\:\mathrm{2}\pi>\theta>\pi \\ $$$$=\frac{\mid\mathrm{1}+{cos}\theta\mid}{\mid{sin}\theta\mid} \\ $$$$=\frac{\mathrm{1}+{cos}\theta}{−{sin}\theta} \\ $$$$=−{cosec}\theta−{cot}\theta \\ $$$$ \\ $$

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